Turbine engines, and particularly gas or combustion turbine engines, are rotary engines that extract energy from a flow of combusted gases passing through the engine onto a multitude of rotating turbine elements or blades, and in some cases, such as aircraft, generate thrust for propulsion.
Gas turbine engines for aircraft are designed to operate at high temperatures to maximize engine efficiency, so cooling of certain engine components, such as a high pressure turbine and a low pressure turbine and associated rotor elements, can be beneficial. Typically, cooling is accomplished by ducting cooler air from high and/or low pressure compressors to the engine components that require cooling. Temperatures in the high pressure turbine can be 1000° C. to 2000° C. and the cooling air from the compressor can be 500° C. to 700° C., enough of a difference to cool the high pressure turbine.